fluid layout for ad?

Hey guys,

I’ve added the following code to my functions.php theme as an action for “amp_wp_post_content_below”:

<amp-ad width=300 height=fluid
    type="doubleclick"
    data-slot="/8804/parceiros/mac_magazine"
    layout="fluid"
    json='{"targeting":{"keyword":["amp"],"campaignuol":["1"],"label":["1-native-rodape"],"native":["1"]}}'>
</amp-ad>

However, when I load any page of my site, the “layout” parameter is automatically changing from “fluid” to “responsive”.

Is this something AMP WP is doing?